1. Field of Application
This invention relates to barbed tape; and more particularly to reinforced barbed tape and a method and equipment for its manufacture.
2. Description of the Prior Art
Intrusive barriers are generally used to prevent intrusion into properties. Such properties may have perimeters with fences, walls and like barriers upon and adjacent to which barbed wire and/or barbed strip, and/or barbed tape are placed to enhance the protection of the property. Often the barbed wire or strips are rolled into a concertina-like configuration.
The security obtainable by such barriers can generally be used for retail, wholesale, industrial storage or any commercial business. Armed forces facilitates, prisons, institutions and governmental facilities requiring high security also widely used such barriers as do livestock containment and other like installations requiring secured facilities. Barbed barriers provide a deterrent of entry or egress of unauthorized or undesired personnel.
The use of barbed wire, barbed strip or tape has existed for many years. Wire with barbs has been employed for quite sometime in the construction of fences, walls and barriers deployed on the ground to inhibit the movement of personnel and vehicles in combat as well as for intruder prevention as previously mentioned.
One form of such intrusion prevention barbed device is a strip or ribbon of the type shown in U.S. Pat. No. 3,224,736 granted on Dec. 21, 1965 D. D. Musgrave for Barbed Strip and in U.S. Pat. No. 3,455,539 granted on July 15, 1969 to J. G. Loofbourrow for Barbed Strip. However, barbed strips and ribbons of this type, especially when rolled into a concertina type configuration, have shown a lack of strength or rigidity. In addition, this construction of barrier has also been easy to break through by use of simple hand-held metal cutting tools.
Other forms of barbed strips or tape have utilized grooves or depressions to add strength and rigidity to the barrier material. But constructions of the type shown in U.S. Pat. No. 186,922 granted on Feb. 6, 1877 to J. Brinkerhoff for Metallic Barbed Fence and the U.S. Pat. No. 386,742 granted on Jul. 24, 1888 to C. J. Grellner for Barbed Fence Strip provide such grooves or depressions in a discontinuous manner thus leaving areas of the strip or ribbon which still lack strength or rigidity and which may still be easily severed by hand-held cutters. Barbed strips or tapes such as shown: in U.S. Pat. No. 187,723 granted to A. J. Nellis on Feb. 27, 1877 for Barbed Fence; in U.S. Pat. No. 214,860 granted on Apr. 29, 1879 to F. Woods for Fencing-Strip; and in U.S. Pat. No. 3,463,455 granted on Jul. 1, 1969 to P. T. Meckel for Helical Barbed Tape Unit, on the other hand, incorporate continuous grooves for adding strength and rigidity to the strip or tape. Such barbed tape constructions, however, would still apppear to provide a tape or strip which may not have sufficient strength or rigidity for the intended purpose. The Nellis type construction, for example, reduces the strength of the groove by striking the barbs from the material in the groove; while the Woods type of barbed strip or tape must provide the groove to only one side of the barbs. A construction as shown by Meckel, on the other hand, provides only a small longitudinal bead or channel which also may not impart an acceptable degree of strength or rigidity to the barrier material. There is, furthermore, no teaching in these patents of how to feasibly and economically obtain the desired groove constructions; especially if the resultant barbed strip is also to be formed into a concertina-type roll or configuration.
Alternatively, available barbed wire or tape constructions provide a reinforcing rib either from the material of the tape itself, or from an additional material attached to the barbed tape material as by welding or other processes. However, the fabrication of such a reinforcing bead from the material of the barbed-tape, requires relatively such as shown in U.S. Pat. No. 3,480,256 granted on Nov. 25, 1969 to G. Simon et al for Barbed Wire, requires relatively complex formation and fabrication equipment and manufacturing processes. On the other hand, the attachment to the barbed tape of a separate reinforcing rib or member may also require relatively complex fabrication equipment and processes. Examples of such barbed wire or barbed tape constructions are shown in: U.S. Pat. No. 3,480,256 granted on Nov. 25, 1969 to Simon et al for Barbed Wire; U.S. Pat. No. 3,763,529 granted on Oct. 9, 1973 D. D. Musgrave for Method of Fabricating Barbed Tape; U.S. Pat. No. 3,916,958 granted on Nov. 4, 1975 to S. Uhi for Process And Apparatus For Producing A Barbed Spiral; and U.S. Pat. No. 4,509,726 granted on Apr. 9, 1985 to W. G. Boggs et al for Barriers. By adding to the relative complexity of the required fabrication equipment and process one adds unduly to the cost of the barbed wire. The added bead of material also adds to the material cost for the barbed tape and adds undesired weight to the resulting barbed tape. This may require more expensive and complex support structure for the barrier which utilizes the bead reinforced barbed tape. Where a separate bead of material is secured to the barbed tape ribbon, especially if a dis-similar material is used, water or moisture may be trapped where the materials come together. This could result in a galvanic action, rusting and weakening of the strength of the barbed tape barrier. Since such barbed barriers are most often disposed outdoors the intrusion of moisture from rain, snow and the formation of ice and dew upon the tape, and the detrimental effects of such moisture intrusion, could and should be expected.
Equipment and processes for drawing metal stock and otherwise fabricating same, such as the equipment and processes shown in: U.S. Pat. No. 2,767,829 granted on Oct. 23, 1956 to K. W. Hallden for Apparatus For Drawing Rod Stock; U.S. Pat. No. 3,373,587 granted on Mar. 19, 1968 to V. N. Shubin et al for Automatic Tube Bending Machines; U.S. Pat. No. 3,668,916 granted on Jun. 13, 1972 to H. C. Ledebur for Drawing Of Metal Tube; and U.S. Pat. No. RE 28,373 granted on Mar. 25, 1975 to F. J. Fuchs Jr. for Apparatus And Method For Continuous Material Feeding And Deformation; are, in fact, relatively complex in construction and operation and costly to purchase, maintain, and operate. Such equipment by drawing the material through the forming tools, and by its inherent other coaction with the material being processed, would be unacceptable to form a strengthened barbed tape and especially to form a barbed tape into a spiral or helical configuration.
Available equipment and processes for fabrication and formation of barbed tape, and for placing the resultant barbed tape into a spiral configuration of the type shown in U.S. Pat. No. 3,916,958 granted on Nov. 4, 1975, to S. Uhl for Process And Apparatus For Producing A Barbed Spiral is unsuitable for forming a strengthened barbed tape unless doing so by adding a rib of material or wire to the tape. The relative cost and complexity of such equipment and process and the detrimental weight, cost, and corrosion susceptibility of such barbed tapes as been reviewed above.
M. R. Mainiero in U.S. Pat. No. 4,02,952 for Apparatus And Method For Forming Barbed Tape discloses a tape which is weakened because it is formed in a polygonal shape. Barbed tape manufactured with Mainiero type equipment, and according to such processes, may also wrinkle when bent to form into a coil, especially because it cannot be produced with a reinforcing rib. Wrinkles so produced may be come areas of high stress and thus weakening the resultant barbed tape barrier.